SEOUL: A new high-quality counterfeit US$100 bill has been found in South Korea, bank officials said yesterday, prompting suggestions that the sanctions-hit North Korea might have resumed forging "supernotes".

Forgery specialists at KEB Hana Bank have confirmed a US$100 note found at a Seoul branch last month was a fake that was almost impossible to distinguish from real banknotes.

"It was the first of a new kind of supernote ever found in the world," Mr Yi Ho Joong, head of KEB Hana Bank's anti-counterfeit centre told AFP.

The forgery is dated 2006.

The same methods including raised and dented printing and no-smudge inks normally used for real banknotes have been applied to the supernote, he said.

"You need facilities worth US$100 million (S$135 million) to produce counterfeit bills of this quality, and no crime ring would invest that much to make fake dollars," he said.